1.3b 20 mph local streets

1.3b 20 mph local streets [Anthony]


30 kmh (20 mph) local streets are an essential aspect in perfecting the overall Dutch systematic safety goal. It is important to create “self-enforcing” 30 kmh roads in residential and school zones, as well as in other areas meant for low volume traffic. Small residential streets should not be used for any kind of distribution to other areas.  Systematic safety can only be established if we accept that humans both make mistakes, and are inherently vulnerable to physical blows from objects with more mass and speed. Therefore, systematic safety aims to not only lower the amount of accidents, but also to minimize the extent of the damage inflicted when an accident occurs.

The zone that I was assigned in Delft encompasses everything East of Oostsingel, South of Tweenmolentjeskade, West of A13, and North of Koepoortstraat. The area surrounding Beukenlaan is covered with many medical offices, an apothecary, as well as a daycare center. Given the fact that this area is an exception to the area as a whole, I have removed it from my analysis.

Although the area sits parallel to A13, it is almost entirely residential, and is not designed for through traffic. Many speed and volume reducing measures had to be put in place in order for traffic to be funneled into the highway, as well as Van Miereveltlaan. The red shaded area as a whole is a bicycle paradise, with the exception of Van Miereveltlaan and Willem Van Aelststraat.


Project Zone Boundaries in Orange: Exception of Yellow Area



Interactive Map Displaying Traffic Calming Devices:



Standout Devices for Speed Control:

Speed Humps/Entrance Tables:

Palamedesstraat Speed Hump:

The most prevalent form of speed reducing infrastructure implemented in the area was by far the speed hump. Although more expensive than the smaller speed cushion, one can argue it is far more effective because it can not be avoided. Nevertheless, speed humps are recognized worldwide to represent reducing speeds in an area. They are used so frequently in this segment that cars are not able to pick up any legitimately high speed even if they wanted to, without damaging their car. This plays into the fact that people will violate the law and speed despite signage, if they are able to do so physically. Speed humps on small local streets also give pedestrians the ability to cross at car eye level, and make it easier for handicap people to cross. However, speed humps do require maintenance to continue performing as they were intended. You can see in the photo above that the speed hump has been flattened by cars, and has lost some of its effectiveness.

Palamedesstraat Entrance Table:

A term trademarked by PFurth himself, an entrance table is an intersection of two roads where the car is raised to sidewalk level before entering/exiting a local street. Van Miereveltlaan is a fast distributor road, which can be seen in the picture above. In order for cars to enter into the local street, they must first break for a raise in elevation similar to a large speed hump. At this point, they are at almost a full 90 degree angle, since they must cross the bicycle lane as well. This drastically increases visibility of crossing pedestrians, but also poses a threat to adjacent cyclists. After being raised to sidewalk level, cars are placed back down to street level to proceed into the local street. This is often the first speed calming device that drivers see in the area coming off of a faster road. It thereby sets the tone that speeding is not possible, and that local streets cannot be used as a cut through.

Permeable Barriers/Dead Ends (For Bikes/Pedestrians):

Leonard Bramerstraat:

As seen in the picture above, permeable barriers have been put in place to demote certain streets for only bike and pedestrian usage. Along with the bollards used to keep cars out, the street itself is marked with a bicycle symbol. Leonard Bramerstraat, featured above, is a completely residential street, which contains a fairly large playground jutting out into the street. With such a large concentration of families playing in the area, it makes a lot of sense to make the street only valuable to the people who live on it. The insertion of permeable barriers on either side of Bramerstraat created a dead end street, which is also marked with signage at the entrance.

Plantagebrug Bridge:

If you looked at an aerial photograph of Plantagebrug Bridge, one would think it was an average car bridge. However, upon closer review, there are clearly bollards placed at either side of the bridge. The Dutch took a bridge more than sufficient for car traffic, and made it a bicycle only bridge. This created the start of a very important bicycle highway, which extends Eastward into the green heart, with amazing scenery and farms. During peak hours, the road is covered with cyclists commuting to or from home. By eliminating certain bridges for cars, the transportation planners further funneled traffic into areas that it should be in, and away from local streets.

Surrounding Roads for Cars to Speed:

Van Miereveltlaan:

As seen above, Van Miereveltlaan looks more like an “American” street than a “Dutch” street. The black asphalt driving lanes are 10 feet wide, and the bike lanes are less than 4 1/2 feet wide. There is even zones of the street where cyclists are sandwiched between 50 km/h traffic and parked cars. Before studying this section, I used to use this street to commute to school. However, I quickly changed my route to the parallel Oostsingel street, because I constantly felt unsafe and unwelcome. Although this street may seem like it doesn’t belong in the area, there is definitely a need for it being there. If every street in my segment was demoted, then people would cut through the local streets because there is no better alternative. But why would someone go 30 km/h with speed humps if they can go 50 km/h on brand new pavement? Although, in my opinion, bikes should not be allowed on this street, the Dutch like options and therefore give cyclists the option to ride in bike lanes.

Street Coloration/Material Change:


Although there were many examples of coloration and material changes in roads to represent different street uses, perhaps the most noteworthy were Oostsingel and Van Miereveltlaan. At one point in history, Oostsingel street was a main car road, but has since been demoted. The street is now comprised of either red or grey brick, which is not the typical pavement material that drivers are accustomed to. Besides being rougher and therefore more uncomfortable to drive on than pavement, drivers in the Netherlands also understand that colors other than black mean bikes and pedestrians. On the contrary, the neighboring Van Miereveltlaan is all asphalt, including the bike lanes (which are just dyed red asphalt). This promoted higher speeds and lets cars know that they are exiting a local street onto a distributor road.

Narrow Roads With Parking:


The picture above depicts Rembrandtstraat utilizing parked cars and narrow roads as speed reducing devices. In many cases, parked cars are seen as a hazard to cyclists because of the risk of getting doored. However, since the area is very residential and people are getting in their cars infrequently, no threat is posed. Parking seemed to be in high demand when I photographed my segment, since every spot was more or less taken. With the addition of parking on both sides, the road narrows to a meager 9 feet wide. That 9 feet gets even narrower when larger vans or poorly parked cars replace the typical dutch compact sedan. Narrow roads increase driver focus and reduce speeds, because no one wants to ruin their expensive car. Also in this case, the cars are essentially becoming the curbs. Hitting a car is much more damaging and costly than brushing up against a curb, and car mirrors protrude into the road. These factors also play into cars wanting to stay off this road, or at least drastically reduce speeds if they turn onto it.


Chicanes on Esdoorlaan:

In the video above, the power of the chicane is demonstrated on a passing van. The entire stretch of Esdoorlaan is a series of chicanes, which force drivers to sway from one side of the road to the other in order to avoid hitting the curb. This method of reducing speed forces the cars to slow down, or risk hitting a curb or loosing control during the turn. I can only imagine that driving on this street is very frustrating, and I would avoid it at all costs. Also, the extended curbs of the chicane provide much needed car parking, and further reduce the likeliness that cars will cross over the curb.  The street is also only 9 1/2 feet wide at the entrances, so there is a combination of traffic calming infrastructure playing out to keep speeds and volume down.

I decided to take a video of the same street, except from a cyclists perspective. By doing this, I observed an aspect of these chicanes that sets it apart from the rest. A cyclist (me in this case) can proceed in a straight line throughout Esdoorlaan without going from side to side like a car would have to. There is just enough space between the bumped out curbs so that cars can’t go straight, but cyclists can. This example of Dutch transportation engineering displays how much thought they put into encouraging cycling and discouraging driving in local areas. In the USA, we don’t understand that if we provide no other realistic option besides the car, people will use their cars. Raised table intersections are also included and can be seen in the video.

Abnormalities from displaying a common goal for the area:

The Wide Street: Willem Van Aelststraat

Willem Van Aelststraat is supposed to be just like every other 30 km/h street that runs from Van Miereveltlaan to Oostsingel, but there are certain aspects that negatively set it apart. Firstly, the street drastically departs from the average 10 1/2 foot lanes of the roads around it, with 16 foot wide lanes. Biking on this road felt like driving amongst cars in the U.S., as cars were clearly speeding. The street also implements the cheaper speed humps, as opposed to the raised table crossings the other streets use. Although the speed humps may be equally as successful in reducing speeds as raised crossings, they do not send as strong of a visual representation to drivers to go slow. The humps on this street seemed to be lengthier and less elevated than other examples I witnessed while taking photos.

Van Miereveltlaan:

This video of Van Miereveltlaan seemed to perfectly demonstrate an exception to the other nearby streets in the area, except this was purposely done. As previously discussed, this street was clearly not designed with the typical dutch cyclist-first mentality. This road was intended to bring cars through the residential areas bordering it on both sides, while still giving bikers the option to use it as well. In this sense, Van Miereveltlaan is a positive contribution to the area, since cars are less incentivised to use local roads instead.

Van Miereveltlaan also poses some serious negatives, which is what really differentiates it from the pack. The video shows a woman crossing a zebra striped crosswalk with a median and the right of way. A car approaches and blows by her, leaving her stranded on the median. The second car goes hard on the breaks to stop for her, and the third car comes close to rear-ending the second car. All of this incident can be linked directly back to the problem of speeding on this road. It is a 50 km/h road, but cars were clearly going faster than that. At those speeds, it becomes so much harder for cars to yield, so they don’t. Cyclists also fall victim to the speeding cars, as they are frequently stuck behind the median for protection. Sadly, this road intersects Aan Het Verlaat, a major bike highway that goes East between Nootdorp and Delfgauw.

USA Application:

East End Avenue: New York City

East End is a North-South Avenue in NYC that only encompasses ten blocks. The road currently has 8 1/2 feet parking on both sides, with 2×2 11 1/2 foot lanes. The area is almost entirely residential, with the exception of one or two stores scattered throughout the ten blocks. The two factors that set East End Avenue apart from any other avenues are: the amount of schools, and Carl Schurz Park. There are four schools along this small stretch, including two schools for pre-primary children. Carl Schurz Park is the backyard for all families who live close to it (including myself), and contains a playground for kids. The boardwalk along the FDR (part of the park) has many joggers, cyclists, and dog walkers throughout the year.

Only 7 streets turn onto East End from York Avenue, because only even streets (with the exception of 79th) run East. All ten streets, from 79th to 89th, directly East of York avenue (ending at either the park or the FDR) should have parking on both sides, with a ten foot one-way lane for travel. They will be reassigned as fietstraats, so bikes can proceed with confidence and not have to pull over or approach a parked car and get doored. East End avenue itself will have all stop lights removed except for the ones on 79th and 86th, as pedestrians would have to cross 4 lanes of traffic without a signal. East End will be reduced to 1+1, with parking on both sides, and a 6 foot one-way cycle track on either side. At all intersections where stop lights have been eliminated, stop signs will be the replacement. I believe this is a more practical set up for the avenue, since many cars wait at lights for a minute when no cars are passing in front of them.

All  intersections of number streets with East End Avenue will have a raised table crossing, with zebra stripes. Parking in front of schools will be eliminated, so that school buses can pull next to the curb to safely drop off kids. On the side streets (the numbered ones between avenues) there will be two speed humps per street. On East End, there will be a speed hump at the halfway point between the table crossings. East End and the numbered streets servicing it are residential and serve no commercial purpose. Cars should not be able to access the FDR from East End, rather only from 79th street (can be photo and sign enforced).


Residential developments become safer/nicer/more desirable when they have enforced local streets. No commercial or bus traffic is better for local streets, and alternative streets should be provided for these sorts of traffic. It is better to have one specific usage for a street, because those streets become more efficient and have less delays. An example of this is infrequent exits on a highway. Saw first hand the better quality of life people live in this environment, despite the few flaws. I witnessed multiple groups of young children without supervision running or biking in the middle of the street, as well as individuals using the sidewalk as a front yard.

Picture Displaying Children at the Leonard Bramerstraat Park

Woman Lounging on the Sidewalk on a Nice Day